The surfaces of food and fodder of both plant and animal origin which are generally available are for the most part more or less seriously contaminated with both physiologically and toxicologically active noxious substances. These substances reach the food in the form of pesticides, fertilizers, preservatives, etc. Further, dirt and other noxious substances unavoidably reach the food and fodder, for example in the form of industrial emissions, fuel residues, oil fumes, and road dust, etc.
Although manual or mechanical washing or scrubbing procedure involving flowing or stagnant, cold or hot water can per se remove a portion of some of the noxious substances adhering to the surface, firmly attached contaminants and the noxious substances are either incompletely removed or not at all.
The most prominent of these noxious substances which are not removed by conventional cleaning are as follows:
1. Polar pesticides PA1 2. Nonpolar pesticides PA1 3. Substituted and unsubstituted hydrocarbons PA1 4. Additives PA1 5. Heavy metals in inorganic form (oxides, carbonates, silicates, soluble salts). PA1 6. General contamination, including insoluble dusts and fibers. PA1 7. Microorganisms. PA1 Anionic surfactants, PA1 Nonionic surfactants, PA1 Sequestering agents, PA1 Buffers, PA1 Reductones, PA1 Disinfectants, PA1 Stabilizers and processing additives.
The environmental contamination of foodstuffs depends in a completely uncontrollable manner on the condition of exposure such as weather and location, on the chemical and physical particularities of the conteminating agents and on the surface characteristics of the foodstuffs.
Further, there is the sequence of sedimentation on the surfaces of the foodstuffs exposed from the time of vegetation until the processing for kitchen and commercial use. By sequence of sedimentation is to be understood the formation of layers on the surface of foodstuffs during these periods of exposure to different elements.